Major interaction on record — check this product against your medications before combining. Based on 16 of 25 ingredients. Check your meds →
Dietary supplement

Liquid Amino Acids Ingredients & Drug Interactions

by Wonder Laboratories

Liquid Amino Acids label
See full label image
Softgel Capsule Category: Amino Acid/protein
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Liquid Amino Acids against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Major

Liquid Amino Acids is a dietary supplement by Wonder Laboratories with 25 active ingredients. Its ingredients are commonly taken for high blood pressure, erectile dysfunction, athletic performance.Based on those ingredients, 803 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are L-Arginine, L-Tryptophan, L-Cysteine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Liquid Amino Acids by Wonder Laboratories

Ask about any prescription or over-the-counter medication and we check it for interactions with Liquid Amino Acids by Wonder Laboratories — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Liquid Amino Acids by Wonder Laboratories

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Aug 13, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 24 of its 24 active ingredients.
  • “Lactalbumin Hydrolysate and Gelatin Blend (Amino Acid/Protein)” is a proprietary blend — the label gives one combined amount (830 mg) without saying how much of each component you get.

This product contains 24 active amino acids and related compounds — including the essential amino acids L-leucine, L-isoleucine, L-valine, L-methionine, L-phenylalanine, L-threonine, L-tryptophan, and L-lysine, plus several others like L-arginine, L-tyrosine, L-glycine, L-serine, and L-cysteine. These are the building blocks your body uses to make proteins and neurotransmitters.

The formula also includes soy lecithin (a phospholipid that supports cell structure), phosphatidylcholine (another membrane component), and a proprietary blend of lactalbumin hydrolysate and gelatin. The inactive ingredients are soybean oil, gelatin, vegetable glycerin, and yellow beeswax — all excipients that help deliver the amino acids in softgel form.

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed

This product doesn't appear to be marketed for a specific use, so we graded its ingredients' overall clinical evidence instead.

Strong

Strong clinical evidence supports its ingredients for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredients' overall clinical evidence instead.
  • On file: Phenylketonuria (PKU) — rated "Effective" (Tyrosine) (Natural Medicines).
  • On file: Cholera — rated "Possibly Effective" (Histidine) (Natural Medicines).
  • On file: Cognitive function — rated "Possibly Effective" (Tyrosine) (Natural Medicines).
  • On file: Herpes labialis (cold sores) — rated "Possibly Effective" (Lysine) (Natural Medicines).
  • On file: Ulcerative colitis — rated "Possibly Effective" (Phosphatidylcholine) (Natural Medicines).

The data we hold shows that individual amino acids in this blend have varying levels of evidence. L-tyrosine is possibly effective for cognitive function and memory, and L-methionine is possibly effective for neural tube birth defects (though that's not a use case for most people taking a general amino acid supplement).

L-phenylalanine is possibly effective for vitiligo, L-glycine for schizophrenia, L-lysine for cold sores, L-serine for schizophrenia, and phosphatidylcholine for ulcerative colitis. Many others in the blend—including L-arginine, L-threonine, L-cysteine, L-proline, L-alanine, and L-histidine—lack sufficient evidence to establish whether they work for the conditions that have been studied.

No single effectiveness rating for the product as a whole appears in our data, so if you're considering it for a specific health goal, ask your doctor or pharmacist whether the science supports that use.

The evidence, ingredient by ingredient L-arginine Methionine Tyrosine Phenylalanine Proline Glycine Aspartic Acid Histidine

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 11 of the 16 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 16 of 16.
  • General safety write-ups exist for 16 of 16.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most of the amino acids in this product are generally well tolerated at typical doses when taken orally. The most common side effects across the ingredients are mild gastrointestinal symptoms — nausea, abdominal pain, diarrhea, and bloating — and occasionally headache, fatigue, or nausea.

L-arginine can lower blood pressure and requires medical supervision for safety; L-phenylalanine and L-tryptophan carry historical safety concerns (phenylalanine is contraindicated in phenylketonuria, or PKU, and L-tryptophan was involved in a contaminated-product incident in the 1980s, though that risk has been addressed). L-methionine at high doses may raise homocysteine levels, a cardiovascular risk factor.

Soy lecithin can trigger allergic reactions in people with soy or egg allergies. For pregnancy and breastfeeding, the picture is mixed.

L-methionine and L-phenylalanine are rated likely safe in pregnancy; L-arginine is possibly safe; but L-phenylalanine supplements should be avoided in pregnancy according to one safety entry, L-tryptophan is possibly unsafe, and L-aspartic acid, L-serine, and L-tyrosine lack sufficient data — talk to your doctor before using this product if you're pregnant or nursing.

Side effects, ingredient by ingredient L-arginine Methionine Tyrosine Phenylalanine Proline Glycine Aspartic Acid Histidine

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 8 of the 16 matched ingredients can interact with medications — Lysine, L-tryptophan, Phenylalanine, L-arginine, Tyrosine, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; Parkinson's medications.
  • For scale: 803 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, double-check the following medication types with your doctor or pharmacist: Parkinson's drugs (levodopa and NMDA antagonists) — this product may reduce their effectiveness, and one interaction is Major. Sedating medications and CNS depressants — L-tryptophan may add to drowsiness.

Blood pressure medications, including ACE inhibitors, ARBs, and other antihypertensives — L-arginine may lower blood pressure further. Antidepressants, especially older MAOIs and serotonergic drugs like SSRIs — phenylalanine and tryptophan may interact.

Diabetes drugs — L-arginine and L-cysteine may increase the risk of low blood sugar. Blood thinners and antiplatelet drugs — L-arginine may increase bleeding risk.

Potassium-sparing diuretics — L-arginine may raise potassium too high. Stomach medications (5-HT4 agonists), thyroid hormones, baclofen, and clozapine — various amino acids may interfere with these.

If you're unsure, ask your pharmacist to run a full check.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with strong clinical evidence behind its ingredients' uses. Major medication interactions have been identified, and safety information is well characterized.

This amino acid blend may be worth considering if you're looking to support general protein intake or specific conditions where individual amino acids show promise (like L-lysine for cold sores). However, it carries several documented drug interactions, most notably with Parkinson's medications, antidepressants, blood pressure drugs, and diabetes medications.

If you take any prescription medication, check your specific drugs on this page before starting. Pregnant or nursing individuals should talk to their doctor first.

Discuss this supplement with your doctor or pharmacist to make sure it's right for you.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 16 of 24 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Oct 22, 2021.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Liquid Amino Acids, straight from the product label.

Brand Wonder Laboratories
Net contents 250 Softgel(s)
Market status On market
Date entered into DSLD Oct 22, 2021
DSLD ID 260350
Product type Amino Acid/protein
Supplement form Softgel Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating), Gluten Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Liquid Amino Acids by Wonder Laboratories, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Softgel(s)
Maximum serving Sizes:
1 Softgel(s)
Servings per container
250
IngredientAmount% DV
Calories10 Calorie(s)--
Calories from Fat5 Calorie(s)--
L-Leucine50 mg--
L-Arginine28 mg--
L-Isoleucine31 mg--
L-Methionine9 mg--
L-Tyrosine13 mg--
L-Phenylalanine17 mg--
L-Valine30 mg--
L-Proline57 mg--
L-Glycine55 mg--
L-Aspartic Acid55 mg--
L-Histidine8 mg--
L-Glutamic Acid93 mg--
L-Threonine34 mg--
L-Tryptophan6 mg--
Total Fat0.5 Gram(s)1%
L-Lysine44 mg--
L-Serine28 mg--
Protein1 Gram(s)1%
Soy Lecithin40 mg--
L-Cysteine13 mg--
Phosphatidylinositol4 mg--
Phosphatidylcholine6 mg--
L-Alanine40 mg--
L-Hydroxylysine1 mg--
L-Hydroxyproline26 mg--
Lactalbumin Hydrolysate and Gelatin Blend (Amino Acid/Protein)830 mg--
Phosphatides24 mg--

Other ingredients: Soybean Oil, Gelatin, Vegetable Glycerin, yellow Beeswax

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Suggested/Recommended/Usage/Directions

Directions: As a dietary supplement, take 1 softgel three times daily, preferably 30 minutes before or after a meal.

Precautions

Tamper Evident: Do not use this product if imprinted foil seal under cap is broken or missing.

Keep out of reach of children.

Caution: If you are pregnant or nursing, consult your physician before taking this product.

Phenylketonurics: Contains Phenyalanine

Contains milk & soy ingredients.

Formulation

Mfg. in a FDA registered facility using Good Manufacturing Practices (GMPs)

Conforms to USP <2091> for weight. Meets USP <2040> disintegration for maximum bioavailability.

Gluten Free

Storage

Keep tightly closed Store at room temperature: 59 degrees-86 degrees F (15 degrees to 30 degrees C).

General Statements

Formula 546

Formula

9 essential 3 Branched-Chain

Free-Form Amino Acids

FDA Statement of Identity

Dietary Supplement

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Liquid Amino Acids by Wonder Laboratories label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Liquid Amino Acids label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Liquid Amino Acids by Wonder Laboratories

These are the 25 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Softgel(s) Dosage formSoftgel Capsule Servings per container250 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Protein

1 Gram(s) per serving

Lactalbumin Hydrolysate and Gelatin Blend (Amino Acid/Protein)

830 mg per serving

Other (inactive) ingredients: Soybean Oil, Gelatin, Vegetable Glycerin, Yellow Beeswax. These complete the product’s ingredient list but are not active constituents.

Interaction report

Liquid Amino Acids by Wonder Laboratories Drug Interactions

Want to check YOUR meds against Liquid Amino Acids?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
803Drugs
256 Major 540 Moderate 7 Minor

Ingredients driving the most interactions

L-Arginine 403
L-Tryptophan 394
L-Cysteine 86
L-Tyrosine 21
L-Phenylalanine 16

Individual Drug Interactions

The ingredients in Liquid Amino Acids interact with 803 drugs. Click any drug to see the details.

8 of the 25 ingredients in Liquid Amino Acids interact with drugs. Each result below shows which ingredient is responsible. L-Arginine L-Tryptophan L-Cysteine L-Tyrosine L-Phenylalanine L-Threonine L-Glycine L-Lysine

Each ingredient & the kinds of drugs it affects

For each ingredient in Liquid Amino Acids with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

L-Arginine9 drug types · 403 drugs

Ace Inhibitors (Aceis)

Theoretically, concomitant use of L-arginine and ACE inhibitors may increase the risk for hypotension and hyperkalemia.
Combining L-arginine with some antihypertensive drugs, especially ACE inhibitors, seems to have additive vasodilating and blood pressure-lowering effects. Furthermore, ACE inhibitors can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients. Theoretically, concomitant use of ACE inhibitors with L-arginine may increases the risk of hyperkalemia.

Likelihood Probable Evidence D
Angiotensin Receptor Blockers (Arbs)

Theoretically, concomitant use of L-arginine and ARBs may increase the risk of hypotension and hyperkalemia.
L-arginine increases nitric oxide, which causes vasodilation. Combining L-arginine with ARBs seems to increase L-arginine-induced vasodilation. Furthermore, ARBs can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients. Theoretically, concomitant use of ARBs with L-arginine may increases the risk of hyperkalemia.

Likelihood Probable Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, concomitant use of L-arginine with anticoagulant and antiplatelet drugs might have additive effects and increase the risk of bleeding.
Preliminary research suggests that L-arginine infusions reduce platelet aggregation in humans. The clinical significance of this effect is unclear.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, concomitant use of L-arginine might have additive effects with antidiabetes drugs.
Preliminary clinical research shows that L-arginine decreases blood glucose levels in patients with type 2 diabetes.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, concomitant use of L-arginine and antihypertensive drugs may increase the risk of hypotension.
L-arginine increases nitric oxide, which causes vasodilation. Clinical evidence shows that L-arginine can reduce blood pressure in some individuals with hypertension. Furthermore, combining L-arginine with some antihypertensive drugs seems to have additive vasodilating and blood pressure-lowering effects.

Likelihood Probable Evidence D
Isoproterenol (Isuprel)

Theoretically, concurrent use of isoproterenol and L-arginine might result in additive effects and hypotension.
Preliminary clinical evidence suggests that L-arginine enhances isoproterenol-induced vasodilation in patients with essential hypertension or a family history of essential hypertension.

Likelihood Probable Evidence D
Potassium-Sparing Diuretics

Theoretically concomitant use of potassium-sparing diuretics with L-arginine may increases the risk of hyperkalemia.
Potassium-sparing diuretics can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients.

Likelihood Possible Evidence D
Sildenafil (Viagra)

Theoretically, concurrent use of sildenafil and L-arginine might increase the risk for hypotension.
In vivo, concurrent use of L-arginine and sildenafil has resulted in increased vasodilation. Theoretically, concurrent use might have additive vasodilatory and hypotensive effects. However, in studies evaluating the combined use of L-arginine and sildenafil for erectile dysfunction, hypotension was not reported.

Likelihood Possible Evidence D
Testosterone

Theoretically, concomitant use of L-arginine and testosterone might have additive effects.
In clinical research, L-arginine increases the level of testosterone in male patients with erectile dysfunction. The clinical significance of this finding is unclear.

Likelihood Possible Evidence D
L-Arginine full monograph & interactions

L-Tryptophan2 drug types · 394 drugs

Cns Depressants

Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Clinical research shows that L-tryptophan can cause fatigue and drowsiness.

Likelihood Probable Evidence B
Serotonergic Drugs

Theoretically, combining L-tryptophan with serotonergic drugs might cause additive serotonergic effects.
L-tryptophan is a precursor to serotonin. Theoretically, combining serotonergic drugs with L-tryptophan might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders.

Likelihood Possible Evidence D
L-Tryptophan full monograph & interactions

L-Cysteine1 drug type · 86 drugs

Antidiabetes Drugs

Theoretically, taking L-cysteine supplements with antidiabetes drugs might increase the risk of hypoglycemia.
Animal research suggests that L-cysteine can have hypoglycemic effects.

Likelihood Possible Evidence D
L-Cysteine full monograph & interactions

L-Tyrosine2 drug types · 21 drugs

Levodopa

Theoretically, tyrosine might decrease the effectiveness of levodopa.
Tyrosine and levodopa compete for absorption in the proximal duodenum by the large neutral amino acid (LNAA) transport system. Advise patients to separate doses of tyrosine and levodopa by at least 2 hours.

Likelihood Probable Evidence D
Thyroid Hormone

Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Tyrosine is a precursor to thyroxine and might increase levels of thyroid hormones.

Likelihood Probable Evidence D
L-Tyrosine full monograph & interactions

L-Phenylalanine3 drug types · 16 drugs

Levodopa

Phenylalanine, especially in high doses, can reduce the effectiveness of levodopa.
Phenylalanine competes with levodopa for carrier-mediated transport into the brain. The resulting reduction in levels of levodopa in the brain can exacerbate tremor, rigidity, and the "on-off" phenomenon in patients with Parkinson disease.

Likelihood Probable Evidence B
Baclofen

Concomitant intake of phenylalanine may reduce the intestinal absorption of baclofen.
Phenylalanine and baclofen share the same intestinal carrier for absorption; phenylalanine competitively inhibits the absorption of baclofen, reducing its plasma levels.

Likelihood Possible Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use of L-phenylalanine and non-selective MAOIs might increase the risk of hypertensive crisis.
L-phenylalanine is metabolized to tyrosine. Some evidence suggests that L-phenylalanine, given with the non-selective MAOI pargyline, might prevent the elimination of tyramine, increasing the risk of hypertensive crisis. However, this was not reported in a small number of patients when using L-phenylalanine with the partially selective MAO-B inhibitor, selegiline.

Likelihood Possible Evidence D
L-Phenylalanine full monograph & interactions

L-Threonine1 drug type · 3 drugs

Nmda Antagonists

Theoretically, threonine might decrease the effects of NMDA antagonists.
Threonine increases central nervous system (CNS) glycine levels. Glycine seems to bind a site on NMDA receptors and enhance the activity of the receptors.

Likelihood Likely Evidence B
L-Threonine full monograph & interactions

L-Glycine1 drug type · 1 drug

Clozapine (Clozaril)

Theoretically, glycine might decrease the effectiveness of clozapine.
One small clinical study in patients with schizophrenia shows that adding glycine to clozapine therapy worsens symptoms of schizophrenia when compared with clozapine alone. The mechanism of this interaction is unclear.

Likelihood Probable Evidence B
L-Glycine full monograph & interactions

L-Lysine1 drug type · 1 drug

5-Ht4 Agonists

Theoretically, lysine may reduce the effects of 5-HT4 agonists.
Animal research suggests that L-lysine is a partial serotonin receptor 4 (5-HT4) antagonist and inhibits diarrhea induced by the 5-HT4 agonist, 5-hydroxytryptophane.

Likelihood Unlikely Evidence D
L-Lysine full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Liquid Amino Acids, from the product label.

Wonder Laboratories

See all Wonder Laboratories products
Name
Wonder Laboratories
Street Address
115 S.C.T. Ct.
City
White House
State
TN
ZipCode
37188
Pharmacist Counseling Corner

Liquid Amino Acids by Wonder Laboratories: Common Questions

Does Liquid Amino Acids by Wonder Laboratories interact with any medications?
Yes. Based on its ingredients, Liquid Amino Acids has a known interaction with 803 medications, including 256 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Liquid Amino Acids contains 25 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take this if I'm pregnant?
The safety data varies by ingredient. L-methionine and L-phenylalanine are rated likely safe or possibly safe, but L-phenylalanine supplements should be avoided in pregnancy according to one safety entry, and several others — including L-tryptophan, L-aspartic acid, L-serine, and L-tyrosine — don't have enough data. Talk to your doctor or pharmacist before taking this product during pregnancy.
Is it safe while breastfeeding?
Again, the data is incomplete across the ingredients. L-methionine, L-phenylalanine, and L-histidine are rated likely safe; others like L-tryptophan are rated unsafe, and many lack sufficient study. Check with your healthcare provider before using this supplement while breastfeeding.
What are the most common side effects?
Mild gastrointestinal symptoms are most common — nausea, abdominal pain, diarrhea, and bloating. Headache, fatigue, and occasional heartburn or insomnia have also been reported with certain amino acids in the blend. Most people tolerate oral amino acids well at typical doses.
Will this help me build muscle or improve athletic performance?
The data we hold shows insufficient evidence that L-tyrosine improves athletic performance (rated possibly ineffective), and the other amino acids in the blend are either possibly ineffective or lack enough study to make a claim. Amino acids are building blocks for muscle, but this product's effectiveness for athletic gains specifically is not established in our data.
Does it contain any allergens?
The product includes soy lecithin, which can trigger allergic reactions in people with soy or egg allergies. It's also made with gelatin. Check the full ingredient list if you have known food sensitivities.
Is this product safe to take with my blood pressure medication?
L-arginine in this product can lower blood pressure and may interact with antihypertensive drugs, ACE inhibitors, and ARBs — adding to their effect and raising the risk of dangerously low blood pressure. Don't start this supplement without checking with your doctor or pharmacist first.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Not sure if Liquid Amino Acids is safe with your meds?

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Liquid Amino Acids label
Go deeper

The Full Monographs Behind Liquid Amino Acids’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

L-arginine

Interacts with 403 drugs

L-arginine is an amino acid that the body uses to make nitric oxide, a substance that helps blood vessels relax and widen. It is popularly used for blood pressure, erectile dysfunction, and...

Read the full L-arginine monograph → Herb & supplement monograph

Methionine

Methionine is an essential amino acid that your body needs for protein building and many basic chemical reactions. Most people get enough from a normal diet, and supplements are generally no...

Read the full Methionine monograph → Herb & supplement monograph

Tyrosine

Interacts with 21 drugs

L-tyrosine is an amino acid your body uses to make brain chemicals like dopamine and norepinephrine. Some studies suggest it may help mental performance during short-term stress, sleep loss,...

Read the full Tyrosine monograph → Herb & supplement monograph

Phenylalanine

Interacts with 16 drugs

Phenylalanine is an essential amino acid the body uses to make brain chemicals like dopamine and norepinephrine. Some people take it for mood, vitiligo, or pain, but the evidence is mostly l...

Read the full Phenylalanine monograph → Herb & supplement monograph

Proline

Proline is a non-essential amino acid that your body can make on its own and that you also get from protein-rich foods. It is a key building block of collagen, but strong human evidence that...

Read the full Proline monograph → Herb & supplement monograph

Glycine

Interacts with 1 drug

Glycine is a non-essential amino acid your body makes on its own and that also appears in protein-rich foods. It is most studied for improving sleep quality, where early research is promisin...

Read the full Glycine monograph → Herb & supplement monograph

Aspartic Acid

Aspartic acid is a common amino acid your body makes on its own and gets from protein-rich foods, so a true deficiency is rare. D-aspartic acid is heavily marketed for boosting testosterone...

Read the full Aspartic Acid monograph → Herb & supplement monograph

Histidine

Histidine is an essential amino acid your body needs to build proteins and to make compounds like histamine and carnosine. Most people get enough from a normal diet, and good-quality researc...

Read the full Histidine monograph → Herb & supplement monograph

Threonine

Interacts with 3 drugs

Threonine is an essential amino acid your body needs but cannot make, so you must get it from food or supplements. Most people get plenty from a normal diet, and high-quality evidence for ta...

Read the full Threonine monograph → Herb & supplement monograph

L-tryptophan

Interacts with 394 drugs

L-tryptophan is an essential amino acid the body uses to make serotonin and melatonin, and people take it to support sleep and mood. The evidence for supplement use is limited and mixed, and...

Read the full L-tryptophan monograph → Herb & supplement monograph

Lysine

Interacts with 1 drug

Lysine is an essential amino acid your body cannot make on its own, so it must come from food or supplements. People most often take extra lysine to try to prevent or shorten cold sores, but...

Read the full Lysine monograph → Herb & supplement monograph

Serine

Serine is an amino acid your body can make on its own and also gets from protein-rich foods, so most people do not need a supplement. L-serine has been studied for certain neurological condi...

Read the full Serine monograph → Herb & supplement monograph

Lecithin

Lecithin is a natural fatty substance found in foods and made by the body that is widely used as a supplement and food emulsifier. Evidence supporting most of its health claims is limited, t...

Read the full Lecithin monograph → Herb & supplement monograph

L-cysteine

Interacts with 86 drugs

L-cysteine is a sulfur-containing amino acid your body uses to make proteins and the antioxidant glutathione. Most people get enough from food, and supplements are usually well tolerated, bu...

Read the full L-cysteine monograph → Herb & supplement monograph

Phosphatidylcholine

Phosphatidylcholine is a phospholipid that is part of every cell membrane and a source of choline. People take it for liver, brain, and gut health, but solid human evidence is limited for mo...

Read the full Phosphatidylcholine monograph → Herb & supplement monograph

Alpha-alanine

Alpha-alanine (usually called alanine) is a non-essential amino acid your body can make on its own and that you also get from protein foods. Most people do not need a supplement, and strong...

Read the full Alpha-alanine monograph →
Sources

Sources & How We Checked

Liquid Amino Acids's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 178 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

L-arginine 66 references
  1. Sapienza MA, Kharitonov SA, Horvath I, et al. Effect of inhaled L-arginine on exhaled nitric oxide in normal and asthmatic subjects. Thorax 1998;53:172-5.
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Aspartic Acid 1 reference
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Lysine 7 references
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Serine 3 references
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Lecithin 9 references
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  9. Electronic Code of Federal Regulations. Title 21, Chapter 1, Subchapter B, Part 184: Direct food substances affirmed as Generally Recognized as Safe. Subpart B - listing of specific substances affirmed as GRAS. Sec. 184.1400 Lecithin. Available at: https:

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L-cysteine 2 references
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  2. Lee S, Han KH, Nakamura Y, et al. Dietary L-cysteine improves the antioxidative potential and lipid metabolism in rats fed a normal diet. Biosci Biotechnol Biochem 2013;77(7):1430-4.

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Phosphatidylcholine 15 references
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  13. Stremmel W, Braun A, Hanemann A, Ehehalt R, Autschbach F, Karner M. Delayed release phosphatidylcholine in chronic-active ulcerative colitis: a randomized, double-blinded, dose finding study. J Clin Gastroenterol 2010;44(5):e101-7. PubMed
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Alpha-alanine 2 references
  1. Amino acids — MedlinePlus (NIH) Source
  2. Dietary Supplements: What You Need to Know — NIH Office of Dietary Supplements Source

See these in context on the Alpha-alanine monograph →

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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

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